The objectives of the proposed research are directed toward refinement of cytopathologic criteria of prognostic value in carcinoma of prostate, and establishment of long-term cultures of neoplastic epithelial cells of prostate. The ultrastructure and histochemistry of prostatic epithelial cells associated with different glandular patterns of carcinoma will be investigated to refine certain cytopathologic criteria of prognostic value. For these studies, samples of carcinoma will be obtained by surgical prostatectomy or by transfurethral resection. Tissue will be fixed in mixed aldehydes and processed for correlative light, transmission, and scanning electron microscopy. The relationship between histologic pattern and content of prostatic acid phosphatase (PAP) will be studied by specific cytochemical techniques. Both explants and isolated epithelial cells of neoplastic prostate will be used to establish long-term cultures in viro. Epithelial cells, as intact acini, will be separated from stromal cells by differential enzymic digestion of prostate tissue. Identification of specific cell types and monitoring of cellular alterations during culture will be carried out by correlative light and electron microscopy, and cytochemistry of PAP. Parallel studies will be undertaken with fresh normal prostate for comparison with human prostatic carcinoma. Normal prostate will be obtained from young patients at the time of death through the Immediate Autopsy Program, Department of Pathology, University of Maryland Hospital.